1; RUN: opt -S < %s -instcombine | FileCheck %s 2 3target datalayout = "e-p1:16:16-p2:32:32-p3:64:64" 4 5@G1 = global i32 42, align 1 6@G2 = global i32 42 7@G3 = global [4 x i8] zeroinitializer, align 1 8 9@A1 = alias i32, bitcast (i8* getelementptr inbounds ([4 x i8], [4 x i8]* @G3, i32 0, i32 2) to i32*) 10@A2 = alias i32, inttoptr (i64 and (i64 ptrtoint (i8* getelementptr inbounds ([4 x i8], [4 x i8]* @G3, i32 0, i32 3) to i64), i64 -4) to i32*) 11 12define i64 @f1() { 13; This cannot be constant folded because G1 is underaligned. 14; CHECK-LABEL: @f1( 15; CHECK: ret i64 and 16 ret i64 and (i64 ptrtoint (i32* @G1 to i64), i64 1) 17} 18 19define i64 @f2() { 20; The preferred alignment for G2 allows this one to foled to zero. 21; CHECK-LABEL: @f2( 22; CHECK: ret i64 0 23 ret i64 and (i64 ptrtoint (i32* @G2 to i64), i64 1) 24} 25 26define i64 @g1() { 27; This cannot be constant folded because A1 aliases G3 which is underalaigned. 28; CHECK-LABEL: @g1( 29; CHECK: ret i64 and 30 ret i64 and (i64 ptrtoint (i32* @A1 to i64), i64 1) 31} 32 33define i64 @g2() { 34; While A2 also aliases G3 which is underaligned, the math of A2 forces a 35; certain alignment allowing this to fold to zero. 36; CHECK-LABEL: @g2( 37; CHECK: ret i64 0 38 ret i64 and (i64 ptrtoint (i32* @A2 to i64), i64 1) 39} 40 41